title: Human auditory cortical activation during self-vocalization.
abstract: During speaking, auditory feedback is used to adjust vocalizations. The brain systems mediating this integrative ability have been investigated using a wide range of experimental strategies. In this report we examined how vocalization alters speech-sound processing within auditory cortex by directly recording evoked responses to vocalizations and playback stimuli using intracranial electrodes implanted in neurosurgery patients. Several new findings resulted from these high-resolution invasive recordings in human subjects. Suppressive effects of vocalization were found to occur only within circumscribed areas of auditory cortex. In addition, at a smaller number of sites, the opposite pattern was seen; cortical responses were enhanced during vocalization. This increase in activity was reflected in high gamma power changes, but was not evident in the averaged evoked potential waveforms. These new findings support forward models for vocal control in which efference copies of premotor cortex activity modulate sub-regions of auditory cortex.
authors.affiliation: Department of Neurosurgery, University of Iowa, Iowa City, Iowa, United States of America. jeremy-greenlee@uiowa.edu
authors.forename: Jeremy D W
authors.initials: JD
authors.lastname: Greenlee
authors.forename: Adam W
authors.initials: AW
authors.lastname: Jackson
authors.forename: Fangxiang
authors.initials: F
authors.lastname: Chen
authors.forename: Charles R
authors.initials: CR
authors.lastname: Larson
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Oya
authors.forename: Hiroto
authors.initials: H
authors.lastname: Kawasaki
authors.forename: Haiming
authors.initials: H
authors.lastname: Chen
authors.forename: Matthew A
authors.initials: MA
authors.lastname: Howard
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001303:Auditory Cortex / Q000503:physiopathology*; D005072:Evoked Potentials, Auditory / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013060:Speech / Q000502:physiology*; D013997:Time Factors; D055815:Young Adult